1. Field of the Invention
The present invention relates to a speed control system for a motor vehicle which serves to automatically change the running speed in accordance with the running conditions.
2. Description of the Prior Art
In a prior art speed control system, the velocity of the vehicle is detected to control running equipment such as a throttle valve in such a way that the velocity will reach a certain desired velocity. Such a speed control system is effective when the vehicle is running at a constant speed for a relatively long period of time, for example, on an expressway.
However, when any such speed-controlled vehicle is following another vehicle running at a relatively low speed in front of the vehicle, or when another vehicle cuts in relatively close in front of the speed-controlled vehicle, the constant running must be interrupted. Whenever such a case occurs, automatic running controlled by the speed control system must be cancelled and changed to ordinary hand operated running. Thus, the prior art speed control system has presented a problem, in that operation thereof includes troublesome steps of cancelling and resuming operation thereof.